1. Field of the Disclosure
The invention relates to resource allocation via wave-front multiplexing and demultiplexing, and particularly to resource allocation in passive optical networks (PON) via wave-front multiplexing and demultiplexing.
2. Brief Description of the Related Art
Most of the Fiber-to-the-Home deployments in recent years have been based on industry standard technologies such as Gigabit Ethernet Passive Optical Networks (GEPON) and Gigabit PON (GPON). Passive Optical Network (PON) is a point-to multipoint network. A PON consists of optical line terminal at the service provider's central office and many number of optical network units near end users. The goal of PON is to reduce the amount of fiber. There are two standards of the Passive Optical Network available, the GPON and the GEPON.
GPON (Gigabit PON) is the evolution of broadband PON (BPON) standard. The protocols used by GPON are ATM, GEM, and Ethernet. It supports higher rates and has more security.
GEPON or EPON (Ethernet PON) is an IEEE standard that uses Ethernet for sending data packets. In current there are 15 million EPON ports installed. GEPON uses 1 gigabit per second upstream and downstream rates. EPON/GEPON is a fast Ethernet over passive optical networks which are point to multipoint to the premises (FTTP) or fiber to the home (FTTH) architecture in which single optical fiber is used to serve multiple premises or users.
The success of these deployments has led to significant innovation in both system architecture and the components that are used to build these systems, and the next generation of passive optical networks will inevitably be far more advanced than what is typically deployed today.
Traditional PON architectures feature one optical feed shared among 32 or more users. In a GPON or GEPON system all subscribers use a common optical wavelength. They share the fiber infrastructure, which is done through time division multiplexing (TDM). Each of those 32 homes transmits over the same fiber, but the time in which they are allowed to “occupy” the fiber is allocated by the optical line terminal (OLT) at the central office. While the equipment in each home is capable of transmitting at over 1,250 Mbps, it can only do so during its allotted time on the fiber, and therefore it is not uncommon for each subscriber in a legacy PON system to only achieve sustained data rates of around 30 Mbps. This concept of many users sharing a common fiber helps minimizing the fiber infrastructure required in an FTTH deployment.